The Goo Goo Dolls’ show Tuesday at Musikfest’s main Steel Stage in South Bethlehem wasn’t perfect. It wasn’t even as good as the group’s show at Reading’s Performing Arts Center in November.

But there still was enough in the 19-song show, which lasted just short of 80 minutes, to make it very good, with some highlights that hit the heights of the group’s previous shows.

The biggest fault was inconsistency: After the group started with oomph on “Sweetest Lie,” singer Johnny Rzeznik’s voice faulted slightly on “Slide,” and there apparently were sound issues, as well – Rzeznik exchanged acoustic guitars mid-song.

But then the start to “Big Machine” was almost unrecognizable, even if it did have lots of energy.

And after an especially good “Naked” had a strong dynamic and nice rock vibe – including Rzeznik’s first lead guitar solo; he had left earlier leads up to a backing guitarist – several of the band’s biggest hits failed to soar the way they should.

“Name” was good, ending with Rzeznik alone on acoustic guitar, and “Black Balloon” was still a lovely, meaningful song, even if not nearly as buoyant – played more as a straight-forward rocker. “Home” also didn’t soar as much, though it still worked.

None of that is meant to be strong criticism. Those all are good songs and even diminished performances were good. It just seemed as if they could have been better.

But the concert seemed to suddenly change in The Goos’ favor when Takac sang “Now I Hear” from the group’s most recent disc, “Something for the Rest of Us.” Takac’s more punky songs often are at odds with the band’s big ballads, but with all of the songs having a more rock take, it fit right in.

And then  Rzeznik took a solo turn, alone and playing acoustic on “Can’t Let Go.” He introduced it by saying, “It might work and it might not. We’ll see.” But perhaps that spontaneity was what was needed: It was Rzeznik’s best singing to that point, and his guitar-playing was elevated, as well.

After that combination of songs, the concert seemed to click. “Let Love In” also didn’t soar as much, but still was good enough to have the crowd clapping along.  Rzeznik seemed to sense a lesser song like “Better Days” needed extra effort, and – the singer far out in front in which spotlights -- his voice finally soared.

“This is our song tonight!” Rzeznik told the crowd.

“Broadway” also was nearer to what it should be, with the backup keyboard player coming out to play a sax solo. When the crowd finished the chorus’ line “waiting for his turn to die,” Rzeznik let loose with a spontaneous “yeah!”  

But perhaps the highlight of the show was when, for the main set’s closing song, The Goo Goo Dolls brought out George Dennehy, an 18-year-old who, born without arms and orphaned in Romania, became an Internet sensation with a video of him playing The Goos’ “Iris” with his feet.

Dennehy joined the group on that song, playing guitar and singing a verse. While it maintained its boiling tension, it also was a celebration, and the crowd joined in on the chorus before giving Dennehy and The Goos a standing ovation. And the teen walked off with Rzeznik.

The group returned for a good, more uplifting “Give a Little Bit,” but the most uplifting moment had passed.

Dennehy earlier played two songs: Arash’s “Broken Angel” alone on guitar and Pink’s “Perfect” with a drummer. He said the latter has “meant a lot to me in the past two years. It doesn’t matter who you are or where you’ve been – you’re special.”

“I’m incredibly blessed,” he told the crowd after performing. “This is beyond anything I ever imagined.”